And believe me, even if you do start with a 10 gallon and are successful keeping your animals, within a couple months you will be buying the 55 gallon anyways! With a small tank like that you are limited to only 2 or 3 fish and that can be really frustrating once you see how many neat animals there are out there! I'd say go for the 55 gallon and get the bare minimum amount of equipment that you can afford, as bkv1997 said (i.e. skip the corals for now, get cheap lights and just the stuff to keep fish only, get some cheap and hardy fish like chromis or clownfish) and once you "master" a fish only tank for a while, you will have a better idea of what animals you want to keep and can upgrade your lights and equipment to be appropriate for inverts. Just because you have a 55 gallon tank doesn't mean you need to fill it all at once.
I started with a 55 gallon and regret that I didn't get a bigger tank in the first place, because at this point it would be way too expensive to get new EVERYTHING to fit a 110 gallon, for example.